Objects to be weighed, such as detergents and confectionary, which are weighed by a combination weigher to have a predetermined weight, are generally packaged by a packaging machine. A structural outline of a conventional combination weigher which measures objects to be weighed is shown in FIG. 12. Moreover, the structural outline of a packaging machine placed below the combination weigher is shown in FIG. 13.
The combination weigher shown in FIG. 12, whose operation is entirely controlled by a control unit 20, is provided with a dispersion feeder 1 at the center of an upper part of the apparatus, the dispersion feeder 1 having conical shape and radially dispersing objects to be weighed supplied from an external feeding device by vibration. Around the dispersion feeder 1, linear feeders 2 are provided for transferring the objects to be weighed sent from the dispersion feeder 1 into each of feeding hoppers 3 by vibration. A plurality of feeding hoppers 3 and weighing hoppers 4 are disposed below the linear feeders 2 and are arranged circularly in such a manner that each feeding hopper 3 and each weighing hopper 4 correspond to the associated one of the linear hopper 2. The feeding hoppers 3 receive the objects to be weighed transferred from the linear feeders 2 and open gates thereof when the weighing hoppers 4 disposed therebelow become empty to feed the objects to be weighed to the weighing hoppers 4. Weight sensors 41 such as load cells are attached to the weighing hoppers 4, and the weight of the objects to be weighed inside the weighing hoppers 4 is measured by these weight sensors 41. A combination of hoppers to discharge the objects to be weighed therefrom is selected from the plurality of weighing hoppers 4 by combination calculation by the control unit 20, and the objects to be weighed are discharged into the collecting chute 6 from the weighing hoppers 4 corresponding to the combination. The collecting chute 6 is provided below the weighing hoppers 4. The objects to be weighed discharged from the weighing hoppers 4 slide down on the collecting chute 6, and is sent out from an outlet provided in a lower portion thereof to the packaging machine (vertical pillow packaging machine) shown in FIG. 13.
In the packaging machine, bags are produced and simultaneously the objects to be weighed discharged from the combination weigher are charged into the bags and packaged. In this packaging machine, a sheet of wrapping material 50 withdrawn from a roll of a wrapping material is caused to surround a tube 51 by a former 52 to form cylindrical shape, is suctioned by a pulldown belt 53 to be transferred downwardly, and the superposed vertical edges of the cylindrically formed wrapping material 50 are sealed (by fusion adhesion) by a vertical sealing machine 54. The weighed objects to be weighed are then charged into the cylindrical wrapping material 50 through the tube 51, and a horizontal sealing machine 55 disposed below the tube 51 seals horizontally across the upper end of a preceding bag and the lower end of the following bag in the transverse direction (by fusion adhesion). By this horizontal sealing, the preceding bag is completed with its upper and lower ends sealed since the lower end of the preceding bag is sealed by the previous horizontal sealing. The center of the horizontal sealed portion is then cut by a cutter built in the horizontal sealing machine 55 so that the preceding bag and the following bag are separated.
Patent document 1: Japanese Unexamined Patent Publication No. S60-161530
Patent document 2: Japanese Examined Patent Publication H8-1395